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The objective of the present work was to prepare organic aerogels using a by-product of oil shale processing as a starting material. Low-density organic aerogels were synthesized via sol-gel polycondensation of formaldehyde (FA) and either 96% 5-methylresorcinol (MR) or the technical mixture named Honeyol™ (H) containing 59.6% of 5-methylresorcinol among other diphenolic compounds, using supercritical CO 2 for drying the gel obtained. Porosity and particle characteristics of MR-FA and H-FA aerogels can easily be controlled by varying the concentrations of precursors and preparation conditions. Less than 4.5-hour drying resulted in MR-FA aerogel characterized by radial shrinkage 2%, density 0.21 g/cm 3 and specific surface area 350 m 2 /g. At the same molar ratios H-FA aerogel had 29% shrinkage, 302 m 2 /g specific surface area and the density as low as 0.10 g/cm 3. The preparation techniques and morphology of MR-FA and H-FA aerogels were compared to resorcinol-formaldehyde, phloroglucinol-formaldehyde and phenol-formaldehyde aerogels.

The low-density organic aerogels formed by the supercritical carbon dioxide drying of 5-methylresorcinol-fotTiialdehyde gels are a good source material for the preparation of low-density carbon aerogels with a homogeneous structure. In our research the supercritical drying process was optimized so that the resulting aerogels would not significanily shrink during the process. The density of the resulting 5-mcthylresorcinol-formaldehyde organic aerogel was as low as 0.1 g/cm\ its specific surface area being more than 350 m^/g. Also, the pyrolysis of the organic aerogel to get carbon material with a proper structure was optimized in relation to the low rate of the evolution of pyrolysis products during the process. The carbon material obtained had a unifonn structure, consisting of sparsely packed particles with a narrow size distribution. The density of carbon aerogels obtained was 0.2 g/cm'. their specific surface area being over 700 mVg; the shrinkage was up lo 30%. It was also found that the porosity of carbon aerogels could be varied by changing the conditions of synthesis. The aerogels obtained were examined using scanning electron microscopy, infrared spectroscopy. and nitrogen adsorption-desorption analysis.

5-methylresorcinol and the technical mixture of oil-shale phenolic compounds were applied for carbon aerogel preparation. Gels, which were prepared via base catalyzed polymerization were dried under supercritical conditions and subsequent pyrolysis of obtained dry aerogels led to carbon aerogels. Activation of carbon aerogel with CO 2 and H 2 O was performed and porosity and the specific surface area of activated carbon aerogels were studied. Langmuir specific surface areas of well over 2000 m 2 /g were achieved and microporosity of carbon aerogel samples was tuneable ranging from below 50% until over 85%. Impregnation with the complex [Pd(C 4 HF 6 O) 2 ] was carried out in supercritical CO 2 using H 2 for a quick reduction of Pd(II) to Pd(0). Eventually, highly porous material decorated with nanoparticles of black palladium was obtained having a homogeneous metal distribution.